I really love the texture you put into the background to give a nice flowing look with the fire and the energy in the face.

The coloring is really nice too, it follows a lot of what the anime has but you expanded it more by making the character in a more realistic look.

Also, hands are pretty correct!

I guess the only thing that could be added, and this is more just a personal nit-pick, is some heavier lines where weight is on Retsuko. Would make parts stand out and fall back within the overall illustration.

Anyways, I really enjoy this piece and hope to see more great work from you!